Myth? Everyone slacks off during 2nd semester.

That may be true for the most part, for a lot of the reasons that have already been mentioned.

People do tend to slack off 2nd semester. Mainly because you're burnt out from first semester. I'm a 2L and I have yet to match the intensity level that I studied at during that first semester of 1L when the pressure was on. I didn't slack off, but it definitely wasn't as intense for me 2nd semester. After you take those first set of law school exams, the mystery is gone. You know what it takes and more importantly, what it doesn't take. I figured out that I don't need to spend hours upon hours in the library briefing cases anymore, because that didn't help for the exam.

^Exactly. I'm spending less time studying this semester than I did last, both because I learned from taking the exams what exactly I need to focus on (and what I don't need to bother with), and because I've naturally gotten faster at taking cases apart and reassembling them, in reduced form, for my own needs.

Of course, I too have taken on new time-consuming tasks--especially Moot Court and Legal Writing, and to a lesser extent the job search--so I can't really say I'm slacking off.